Abstract : This report covers results of research addressing the fracture and crack growth behavior of solid propellants in support of structural integrity methodology for the failure response of solid propellant rocket motors. The effects of damage, temperature, and strain rate on local behavior near the crack tip and crack growth behavior in solid propellants were investigated. Numerical modeling techniques were used to determine the local strain fields near the crack tip and the fracture parameters associated with crack growth. The results of both experimental and analytical analyses were evaluated and discussed.